Sign up to receive free email alerts when patent applications with chosen keywords are publishedSIGN UP

Abstract:

The invention relates to an oat suspension, a process for preparation
thereof and a powder made thereof. The suspension and the powder can be
used for preparing drinks and other non-dairy products with improved
sensory properties.

Claims:

1. An oat suspension, optionally fermented, containing enzymatically
treated oat raw material, water and optionally at least one food
ingredient, characterised in that the suspension comprises on dry weight
basis: glucose 8-75%, preferably 15-70%, more preferably 20-65%, and most
preferably 25-60%, maltose 0-15%, preferably 0-10%, more preferably 0-8%,
and most preferably 0-5%, and β-glucan, originating from the oat raw
material, at most 3.0%, preferably at most 2.0%, more preferably at most
1.0%, still more preferably at most 0.5%, and most preferably no
β-glucan originating from the oat raw material.

2. The suspension according to claim 1, characterised in that it has a
ratio of glucose to maltose of 1:1-99:1, preferably 2:1-25:1, more
preferably 2.5:1-20:1, still more preferably 4:1-15:1, and most
preferably 5:1-10:1.

3. The suspension according to claim 1 characterised in that it comprises
protein, originating from the oat raw material, having a degree of
hydrolysis of at most 10%, preferably at most 8%, more preferably at most
6%, still more preferably at most 4%, still more preferably at most 2%,
and most preferably 0%.

4. The suspension according to claim 1, characterised in that it
comprises protein, originating from the oat raw material, 0.1-20%,
preferably 0.5-15%, more preferably 1-12%, and most preferably 2-10% on
dry weight basis.

5. The suspension according to claim 1, characterised in that it
comprises non-fibre oligosaccharides 1-40%, preferably 2-30%, more
preferably 3-20%, and most preferably 4-10% on dry weight basis.

6. The suspension according to claim 1, characterised in that it
comprises starch 0-25%, preferably 0-20%, more preferably 0-15%, and most
preferably 0-10% on dry weight basis.

7. The suspension according to claim 1, characterised in that it
comprises enzymatically treated oat raw material 15-100%, preferably
25-99%, more preferably 40-98%, still more preferably 60-97%, and most
preferably 80-96% on dry weight basis.

8. The suspension according to claim 1, characterised in that it
comprises enzymatically treated oat raw material 2-30%, preferably 3-20%,
more preferably 4-15%, and most preferably 5-10% by weight.

9. The suspension according to claim 1, characterised in that it has a
viscosity of at most 700 mPas, preferably at most 500 mPas, more
preferably at most 300 mPas, and most preferably at most 100 mPas.

10. The suspension according to claim 1, characterised in that the food
ingredient is at least one selected from the group consisting of food
additives; vegetable, fruit and/or berry materials; and nutritionally
beneficial components, such as dietary fibre, purified protein, plant
sterol and/or plant stanol, omega-3 fatty acid, probiotics, vitamin, and
mineral.

11. The suspension according to claim 10, characterised in that the
dietary fibre is at least one selected from the group consisting of
polydextrose, purified β-glucan, fructo-oligosaccharide, pectin,
alginate, carrageenan and gum, e.g. arabic, guar, xanthan, gellan or
locust bean gum.

17. A process for the preparation of an oat suspension according to claim
1 including the steps of (a) preparing a mixture of oat raw material and
water; (b) milling the oat raw material; (c) treating the oat raw
material with at least one α-amylase and at least one enzyme
producing glucose; (d) inactivating the enzymes; (e) removing insolubles
at least partly to form an oat suspension; (f) optionally adjusting dry
matter content of the suspension; (g) optionally homogenising,
pasteurising and/or UHT treating the suspension; (h) optionally
fermenting the suspension; and (i) optionally adding at least one food
ingredient to the suspension, characterised in that: the oat raw material
is milled so that at least 50%, preferably at least 65%, more preferably
at least 80% and most preferably all of the particles are larger than 200
μm, and enzymes with substantially no protease activity are used.

18. The process according to claim 17, characterised in that the oat raw
material is at least one selected from the group consisting of rolled
oats, whole oat flour, endosperm oat flour and oat bran, preferably at
least one selected from the group consisting of rolled oats and whole oat
flour.

19. The process according to claim 17, characterised in that the enzyme
producing glucose is at least one selected from the group consisting of
glucoamylase (EC 3.2.1.3), α-glucosidase (EC 3.2.1.20),
amylo-1,6-glucosidase (EC 3.2.1.33) and oligo-1,6-glucosidase (EC
3.2.1.10), preferably glucoamylase (EC 3.2.1.3).

20. The process according to claim 17, characterised in that step B
precedes step A, that step D precedes step E and/or that step I precedes
step H or G.

Description:

FIELD OF INVENTION

[0001] The invention relates to an oat suspension which has good sensory
properties, to the preparation thereof and to a powder prepared from the
suspension, and to drinks and other food products containing the
suspension or the powder.

BACKGROUND OF THE INVENTION

[0002] Oats have traditionally been consumed mainly as breakfast cereals
and in bakery products. During the last years new type of oat products
have been developed. Examples are non-dairy products, such as oat milk
and other oat drinks as well as oat creams, desserts and fermented
products such as yoghurt-like products (i.e. non-dairy yoghurt).

[0003] Oat milks and other oat drinks have most commonly been prepared by
treating oat raw material with enzymes to break down the chemical
constituents, especially starch. Several processes have been described.
Starch is degraded into sugars, especially maltose. The other
constituents, like proteins and fibres, may remain intact or may be
enzymatically degraded as well.

[0004] WO 95/07628 describes a homogenous and stable cereal suspension
having the taste and aroma of natural oats and comprising intact
β-glucans. The suspension is prepared by treating oatmeal suspension
first with β-amylase, which specifically generates maltose units and
has no glucanase and proteinase effect, and thereafter with
α-amylase, which specifically generates maltose units and has no
glucanase and proteinase effect.

[0005] WO 00/22938 provides a method for producing cereal suspensions
having the aroma and/or flavor of natural cereals. The method includes
treating a cereal substrate suspension with an enzyme preparation which
comprises at least one hydrolase having the ability to hydrolyse
a-glycosidic bonds and having no glucanase and proteinase effect. The
hydrolase may be selected from the group consisting of β-amylase,
α-amylase, amyloglucosidase and pullulanase, with the proviso that
when the enzyme preparation comprises β-amylase or α-amylase
there is always a mixture of at least one other of the α-glycosidic
hydrolases.

[0006] WO 02/065855 discloses a non-dairy, ready-to-use milk substitute
prepared by the steps, which comprise: (i) providing a cereal suspension;
(ii) providing a starch degrading enzyme composition devoid of
β-glucanase and proteinase activity comprising a α-amylase and
β-amylase, and (iii) treating said cereal suspension with said
enzyme composition by introducing the β-amylase and the
α-amylase simultaneously to said cereal suspension.

[0007] WO 03/075683 discloses starch modified oat and a preparation method
thereof. The starch modified oat has a glucose content of at least 2
g/100 g on dry weight basis and β-glucan content of at least 4 g/100
g on dry weight basis. The starch modified oat contains also maltose of
at least 30 g/100 g on dry weight basis. The starch modified oat is
prepared by using α-amylase(s) and/or carbohydrase(s) in the first
hydrolysis step and β-amylase(s) in the second hydrolysis step.

[0008] U.S. Pat. No. 4,377,602 discloses a preparation of hydrolysed
products from whole grain. Whole grain is treated with a proteolytic
enzyme and an amylase to transform protein and starch which is insoluble
in water into water soluble products.

[0009] U.S. Pat. No. 5,723,162 describes a non-dairy frozen confection
which is formed from a syrup using conventional techniques. The syrup is
produced by liquefying and saccharifying a starch source, which is
primarily oat flour or waxy barley hybrid flour.

[0010] U.S. Pat. No. 6,685,974 discloses a process for preparing an
oat-based functional syrup. The process includes milling an oat material
to produce a base formulation. Material having a granulation of more than
U.S. #100 mesh is separated from the base formulation. The base
formulation is then blended with water to form a slurry. Effective
amounts of α-amylase enzyme and glucoamylase enzyme are mixed into
the slurry. The slurry is then cooked to convert the slurry into a syrup.

[0011] WO 00/30457 discloses a process for preparing an oat-derived base
comprising: preparing an oat based slurry having a solids content of
between 5 and 45% oat substrate by weight, said oat substrate containing
β-glucan and oat starches; heating the slurry to gelatinize at least
a portion of the oat starches; adding an effective amount of at least an
enzyme that has substantially no β-glucanase activity and digesting
to the desired endpoint; and inactivating said enzyme to yield the liquid
oat base.

[0012] Despite these different methods to prepare oat suspensions or
syrups for use in e.g. non-dairy milks and other drinks and food products
there is still a need for new improved methods and products. Almost all
above mentioned processes aim at releasing the β-glucan from the oat
raw material into the oat suspension. This intact or high molecular
weight β-glucan is known to remarkably increase viscosity and to
make the mouthfeel of the product slimy, which are disadvantages in
drinks, especially those intended to be consumed as non-dairy milk. Other
disadvantages with the known oat suspensions are the strong taste of oat
and the dark colour such as greyish or even brownish off-colour. There
have been attempts (U.S. Pat. No. 6,685,974) to diminish the dark colour
and the strong oat taste by removing substantial portions of the bran
before the actual enzymatic hydrolysis. This was accomplished by milling
to a small particle size and removing the fraction rich in bran, i.e. the
larger particles. However, this restricts the oat raw material which can
be used for making the suspension. The thereby produced suspension was
also too sweet to be used as non-dairy milk. Thus, also suitable
sweetness of an oat suspension consumed as non-dairy milk is desirable to
obtain a pleasant taste of the suspension. Oat suspensions having high
glucose content have been used for preparation of sweet confections and
sweet flavoured drinks, but they are too sweet to be used as non-dairy
milk. On the other hand, known oat suspensions having high maltose
content are less sweet, but their strong taste of oat is not appealing to
the consumers.

[0013] Therefore, there is still a need for oat suspensions with good
sensory properties, including good structure, pleasant mouthfeel, no or
only a mild oat taste, light colour, and suitable sweetness, and also for
a simple method for preparation of such oat suspensions.

SUMMARY OF THE INVENTION

[0014] The present invention provides an oat suspension suitable to be
used as non-dairy milk as such or diluted, and/or further including
suitable food ingredients. The suspension can also be in the form of
flavoured oat drinks as well as other drinks and food products and/or it
can be fermented.

[0015] Compared to prior art the oat suspension of the present invention
has improved sensory properties, i.e. taste, structure, mouthfeel and
colour. The taste is good as the suspension has practically no or only
mild oat taste without being sugary. The colour is very light which is
beneficial especially in oat suspensions consumed as non-dairy milk. The
oat suspensions have pleasant mouthfeel and structure, i.e. have low
viscosity and no sliminess.

[0016] The invention is also directed to a process for preparing the oat
suspension by enzymatic treatment of suspended oat raw material.

[0017] The invention is further directed to powders prepared from the oat
suspensions.

[0018] Even further the invention is directed to non-dairy products
containing the oat suspension or the powder.

[0019] The characterising features of the present invention are set forth
in the claims.

DETAILED DESCRIPTION OF THE INVENTION

[0020] The present invention provides an oat suspension containing an
enzyme modified oat raw material with good sensory properties such as
good taste, colour, structure and mouthfeel. Surprisingly, it was found
that this may be achieved by certain selections in the composition of the
suspension.

[0022] The oat suspension according to the invention is produced by
enzymatically treating a mixture of oat raw material and water in such a
way that at least part of the starch is hydrolysed to glucose and other
sugars.

[0023] The invention is directed to an oat suspension, optionally
fermented, containing enzymatically treated oat raw material, water and
optionally at least one food ingredient, characterised in that the
suspension comprises on dry weight basis 8-75% glucose, 0-15% maltose,
and at most 3.0% β-glucan originating from the oat raw material.

[0024] The glucose content of the oat suspension according to the
invention is sufficient to provide suitable sweetness but not too high to
taste sugary. The glucose content in the suspension is 8-75%, preferably
15-70%, more preferably 20-65%, and most preferably 25-60% on dry weight
basis (dwb).

[0025] In addition to glucose, the suspension preferably also comprises
maltose in an amount of 0-15%, preferably 0-10%, more preferably 0-8% and
most preferably 0-5% (dwb). Low amount of maltose may exist, e.g.
0.1-10%, preferably 0.2-8%, more preferably 0.3-6%, still more preferably
0.4-4%, and most preferably 0.5-3 (dwb). A suitable ratio of glucose to
maltose in the suspension is 1:1-99:1, preferably 2:1-25:1, more
preferably 2.5:1-20:1, still more preferably 4:1-15:1, and most
preferably 5:1-10:1. This provides a suspension with a balanced sweetness
appealing to consumers.

[0026] The β-glucan content in the oat suspension, originating from
the oat raw material, should be very low, i.e. at most 3.0%, preferably
at most 2.0%, more preferably at most 1.0%, still more preferably at most
0.5% (dwb), and most preferably there is no β-glucan originating
from the oat raw material in the suspension. This feature of the
suspension will give it good sensory properties, including suitable
viscosity and lack of sliminess.

[0027] Further, it was found that the protein originating from the oat raw
material should have a degree of hydrolysis of at most 10%, preferably at
most 8%, more preferably at most 6%, still more preferably at most 4%,
still more preferably at most 2%, and most preferably 0% in the
suspension. The suspension preferably contains such protein in an amount
of 0.1-20%, more preferably 0.5-15%, still more preferably 1-12%, and
most preferably 2-10% (dwb). These features will both have a positive
impact on the sensory properties, especially on the taste of the
suspension.

[0028] The protein content can be analysed by the Kjeldahl method. The
degree of hydrolysis of the protein is the extent to which peptide bonds
are broken by an enzymatic hydrolysis reaction. The degree of hydrolysis
can be analysed by the OPA method (Nielsen P. M. et al., Journal of Food
Science, 2001, vol. 66, no 5, 642), which is based on the reaction of
primary amino groups with o-phthaldialdehyde (OPA).

[0029] As used here "non-fibre oligosaccharides" refers to
oligosaccharides that have a degree of polymerisation (DP) between 3-20
and are not resistant to digestion and absorption in the human small
intestine. Most of the non-fibre oligosaccharides in the oat suspension
are derived from starch that has been at least partly degraded in the
preparation process of the oat suspension. Also other non-fibre
oligosaccharides may be present. Non-fibre oligosaccharides can also
raise the viscosity of the oat suspension. Therefore, the amount of such
oligosaccharides in the suspension should preferably be limited to 1-40%,
more preferably to 2-30%, still more preferably to 2.5-25%, still more
preferably to 3-20%, still more preferably to 3.5-15%, and most
preferably to 4-10% (dwb).

[0030] All starch in the oat raw material is not necessarily hydrolysed.
Thus there may be 0-25%, preferably 0-20%, more preferably 0-15%, and
most preferably 0-10% (dwb) starch in the suspension. Low amount of
starch may exist, e.g. 0.1-20%, preferably 0.2-15%, more preferably
0.3-10%, and most preferably 0.4-5% (dwb).

[0031] The sugar and non-fibre oligosaccharide content and profile of the
oat suspension can be analysed by an ion chromatographic method (Dionex
CarboPac PA-100 column, pulse amperometric detector ED50). The starch can
be analysed by AOAC method 996.11 and β-glucan by AOAC method
995.16.

[0032] The oat suspension according to the invention comprises
enzymatically treated oat raw material 15-100%, preferably 25-99%, more
preferably 40-98%, still more preferably 60-97%, and most preferably
80-96% on dry weight basis.

[0033] The amount of enzymatically treated oat raw material in the
suspension is 2-30%, preferably 3-20%, more preferably 4-15%, and most
preferably 5-10% by weight.

[0034] All oat suspensions according to the invention that are drinkable
have a viscosity of at most 700 mPas, preferably at most 500 mPas, more
preferably at most 300 mPas, and most preferably at most 100 mPas. The
viscosity can be measured at 20° C. using a Sine-wave Vibro
Viscometer, model SV-10 (A&D Company, Ltd). Therefore, e.g. spoonable
non-dairy yoghurts and ice-cream like products may have a higher
viscosity.

[0035] The dry matter content of the oat suspension can be adjusted by
diluting the suspension with water or by evaporating it to a wanted
concentration.

[0036] The oat suspension according to the invention may be fermented,
preferably with lactic acid bacteria or bifidobacteria. This enables the
oat suspension to be e.g. a spoonable or drinkable non-dairy yoghurt.

[0037] The oat suspension can contain only the enzymatically treated oat
raw material and water. However, at least one food ingredient may be
added. The optional food ingredient may include food additives such as
stabilisers, emulsifiers, sweetening agents (e.g. saccharose, starch
syrup, fructose, aspartame, sorbitol, sodium cyclamate, acesulfame K and
sucralose), preservatives, flavourings (e.g. vanilla, fruit or berry
flavors), fats, oils, cocoa, or any mixtures thereof. The optional food
ingredient may include vegetable, fruit and/or berry materials, such as
vegetable juice or puree; fruit juice, puree, jam or marmalade; berry
juice, puree, jam or marmalade; or any mixtures thereof. The optional
food ingredient may include nutritionally beneficial components such as
vitamins, minerals, plant sterols and/or plant stanols, omega-3 fatty
acids, dietary fibres, purified proteins, probiotics or any mixtures
thereof. An example of vitamins is vitamin D. Of minerals, especially
calcium is preferred. If calcium is added, its concentration is
preferably adjusted to at least the same level as in dairy milk. Plant
sterols and/or plant stanols may preferably be added in a form of plant
sterol ester and/or plant stanol ester. In this specification the plant
sterols include 4-desmethyl sterols, 4-monomethyl sterols and
4,4-dimethyl sterols (triterpene alcohols) and the plant stanols include
4-desmethyl stanols, 4-monomethyl stanols and 4,4-dimethyl stanols. As
used here, the term "plant sterol ester" or "plant stanol ester" refers
to plant sterols or plant stanols having at least 60%, preferably at
least 85%, most preferably at least 95% of the plant sterols and/or plant
stanols in esterified form. In this invention the plant sterol esters
and/or plant stanol esters are esterified with an organic acid,
preferably with fatty acids, most preferably with vegetable oil based
fatty acids, such as fatty acids from sunflower oil or soybean oil. Oils
rich in omega-3 fatty acids include fish oils and vegetable oils such as
camelina oil, linseed oil and rapeseed oil, and their fatty acids may
preferably be used in the plant sterol ester and/or plant stanol ester.
Preferred oils are of vegetable origin.

[0038] The dietary fibre is preferably soluble dietary fibre. The term
"soluble dietary fibre" as used herein refers to non-starch
polysaccharides characterised as being water soluble. The soluble dietary
fibre is added to the ready oat suspension, after the enzymes have been
inactivated and the insoluble fraction of oat raw material removed.
Examples of suitable soluble dietary fibres are purified β-glucan,
polydextrose, inulin and other fructo-oligosaccharides, pectin and its
derivatives, arabinoxylans, arabinogalactans, psyllium, alginates,
carrageenan and vegetable gums such as konjac gum, xanthan gum, guar gum
(guaran gum), locust bean gum, gum tragacanth, arabic gum and gellan gum.
By adding soluble dietary fibre afterwards, a product with high fibre
content can be achieved without compromising the sensory properties. A
preferred soluble dietary fibre is purified β-glucan, especially
purified cereal β-glucan, such as oat or barley derived
β-glucan. The term "purified β-glucan" as used here refers to
soluble β-glucan preparations that do not cause off-colours or
cereal taste to the oat suspension. Preferably low molecular weight
β-glucan is used. Preferably the β-glucan has an average
molecular weight of at most 500 000 Daltons, more preferably at most 200
000 Daltons. The molecular weight can be determined e.g. by size
exclusion chromatography.

[0039] If an oat suspension with high protein content is desired, purified
protein may be added to the oat suspension. The purified protein is added
to the ready oat suspension, after the enzymes have been inactivated and
the insoluble fraction of oat raw material removed. Examples of suitable
proteins are proteins of plant origin, especially cereal proteins and
soybean protein. The term "purified protein" as used here refers to
proteins and hydrolysis products thereof that do not cause off-colours
(such as brownish or greyish colour) or off-flavours (such as displeasing
cereal flavour) to the oat suspension. By adding purified proteins
afterwards, an oat suspension with high protein content can be achieved
without compromising the sensory properties.

[0040] The suspension can be in the form of various non-dairy edible
compositions, in e.g. non-dairy milk, non-dairy cream, non-dairy
flavoured drinks, non-dairy desserts such as ice-cream-like products, and
fermented non-dairy products such as yoghurt-like products (i.e.
non-dairy yoghurt). The compositions are suitable also to people allergic
to dairy components.

[0042] The suspension is especially suitable for use as non-dairy milk
because of the favourable sensory properties. A preferred non-dairy
edible composition is therefore a non-dairy milk comprising the oat
suspension according to the invention. The non-dairy milk contains at
least one food ingredient selected from the group consisting of salt,
preferably in an amount of 0.01-0.3 g, vegetable oil, preferably in an
amount of 0.1-5 g, calcium, preferably in an amount of 0.05-0.3 g,
vitamin D, preferably in an amount of 0.1-2 mg, and stabiliser,
preferably in an amount of 0.01-2 g per 100 g non-dairy milk. Preferably
the non-dairy milk contains all these food ingredients. The non-dairy
milk can also contain plant sterol and/or plant stanol, preferably in an
amount of 0.1-10 g per 100 g non-dairy milk.

[0043] Another preferred non-dairy edible composition is a non-dairy
cream, such as cooking cream, whipping cream or dessert cream (such as
vanilla custard), comprising the oat suspension according to the
invention. The non-dairy cream contains at least one food ingredient
selected from the group consisting of sweetening agent such as saccharose
and/or starch syrup, preferably in an amount of 0.1-10 g; acidifier,
preferably in an amount of 0.05-1 g; emulsifier, preferably in an amount
of 0.01-2 g; stabiliser, preferably in an amount of 0.1-5 g; salt,
preferably in an amount of 0.01-0.3 g; flavouring such as cream/milk
arome or vanilla, preferably in an amount of 0.01-1 g; and vegetable
oil/fat, preferably in an amount of 1-40 g per 100 g non-dairy cream. The
non-dairy cream can also contain plant sterol and/or plant stanol,
preferably in an amount of 0.1-10 g per 100 g non-dairy cream.

[0044] Still another preferred non-dairy edible composition is a non-dairy
flavoured drink comprising the oat suspension according to the invention.
The non-dairy flavoured drink contains at least one food ingredient
selected from the group consisting of sweetening agent such as
saccharose, preferably in an amount of 0.1-10 g; cocoa powder, preferably
in an amount of 0.5-5 g; vegetable oil, preferably in an amount of 0.1-5
g; calcium, preferably in an amount of 0.05-0.3 g; stabiliser, preferably
in an amount of 0.01-2 g; salt, preferably in an amount of 0.01-0.3 g;
vitamin D, preferably in an amount of 0.1-2 μg; flavouring, preferably
in an amount of 0.01-1 g; vegetable, fruit and/or berry materials,
preferably in an amount of 1-30 g; soluble dietary fibre, preferably in
an amount of 0.01-10 g; and plant sterol and/or plant stanol, preferably
in an amount of 0.1-10 g per 100 g non-dairy flavoured drink. By
flavoured drink is meant a drink containing any component delivering
flavour to the drink, such as cocoa; flavouring; and vegetable, fruit
and/or berry materials.

[0045] Yet another preferred non-dairy edible composition is a spoonable
or drinkable non-dairy yoghurt comprising the oat suspension according to
the invention. Preferably, the non-dairy yoghurt is prepared by
conventional fermenting techniques. The non-dairy yoghurt contains at
least one food ingredient selected from the group consisting of
sweetening agent such as saccharose, preferably in an amount of 0.1-10 g;
emulsifier, preferably in an amount of 0.05-1 g; stabiliser, preferably
in an amount of 0.05-10 g; flavouring, preferably in an amount of 0.01-1
g; vegetable oil/fat, preferably in an amount of 0.5-5 g; purified
protein such as soy bean protein isolate, preferably in an amount of
0.1-10 g; fruit and/or berry materials, preferably in an amount of 1-40
g; soluble dietary fibre, preferably in an amount of 0.01-10 g; and plant
sterol and/or plant stanol, preferably in an amount of 0.1-10 g per 100 g
non-dairy yoghurt. Examples of suitable bacteria that can be used for the
preparation of the non-dairy yoghurt are the cultures used conventionally
for yoghurt preparation, such as lactic acid bacteria and bifidobacteria.

[0046] The invention also relates to the preparation of an oat suspension
usable in oat drinks such as oat milk with good taste, colour, structure
and mouthfeel. The suspension may also find use in other kind of edible
non-dairy compositions such as non-dairy cream, yoghurt-like products and
ice-cream-like products.

[0047] The suspension is prepared by enzymatic treatment of a mixture of
oat raw material in water. Surprisingly, it was found that an oat
suspension with desired properties may be produced with careful selection
of the type of enzymes and the particle size of the raw material.

[0048] Thus, the invention relates to a process for the preparation of an
oat suspension including the steps of

A preparing a mixture of oat raw material and water B milling the oat raw
material C treating the oat raw material with at least one
α-amylase and at least one enzyme producing glucose D inactivating
the enzymes E removing insolubles at least partly to form an oat
suspension F optionally adjusting dry matter content of the suspension G
optionally homogenising, pasteurising and/or UHT treating the suspension
H optionally fermenting the suspension and I optionally adding at least
one food ingredient to the suspension characterised in that the oat raw
material is milled so that at least 50% of the particles are larger than
200 μm and enzymes with substantially no protease activity are used.

[0049] The oat raw material may contain all material in the dehulled
grain, i.e. not only the endosperm fraction but also the bran part may be
present as the process does not release too much β-glucan to the
suspension. Thus, rolled oats, whole oat flour, endosperm oat flour, oat
bran and their mixtures are usable as oat raw material. Preferably rolled
oats or whole oat flour are used as oat raw material in the process
according to the invention.

[0050] It was surprisingly found that by using a particle size of the oat
raw material that is large enough good sensory properties of the
suspension were achieved. At least 50%, preferably at least 65%, more
preferably at least 80% and most preferably all of the particles are
larger than 200 μm when the enzymatic treatment is started. This may
require milling of the oat particles to a suitable particle size before
mixing with water, during mixing or after the particles have been
suspended in water.

[0051] The mixture of oat raw material of suitable particle size
distribution and water has a dry matter content from 3 to 50%, preferably
5-40%, more preferably 8-30% and most preferably 10-25% when the
enzymatic treatment is started.

[0052] The mixture is treated enzymatically to degrade at least part of
the starch in the particles mainly to glucose but also to other sugars,
e.g. maltose may be present.

[0053] The mixture is treated with at least one α-amylase and at
least one enzyme producing glucose followed by deactivation of the
enzymes. Preferably, the enzymes are allowed to function simultaneously.
It is also possible to treat the oat material first with α-amylase,
deactivating it and then repeating the same with the enzyme producing
glucose. However, this latter possibility is more complicated and time
consuming

[0054] The amount of enzymes and the process conditions e.g. temperature
and reaction time may vary depending e.g. on the activity of the enzymes
and the oat material content. However, the skilled man is competent to
determine suitable parameters.

[0055] The enzymes are inactivated when a suitable consistency of the
suspension has been achieved. The inactivation may take place e.g. by
adjusting the pH or preferably by raising the temperature of the
suspension e.g. to 80-150° C., and preferably to 80-130° C.
for a sufficient time.

[0056] The enzyme producing glucose hydrolyses starch in the oat raw
material and especially dextrins or oligosaccharides formed by the
α-amylase(s) to glucose. The enzyme producing glucose is not an
α-amylase according to the definition of this invention.
Non-limiting examples of the enzymes producing glucose are glucoamylase
(EC 3.2.1.3), α-glucosidase (EC 3.2.1.20), amylo-1,6-glucosidase
(EC 3.2.1.33) and oligo-1,6-glucosidase (EC 3.2.1.10). Preferably the
enzyme producing glucose is glucoamylase (EC 3.2.1.3), which catalyses
the release of successive glucose units from the non-reducing end of
dextrin and oligosaccharide chains by hydrolysing both linear
(1,4-α-D) and branched (1,6-α-D) glucosidic bonds. The
enzymes may be from microbial, animal or plant origin and may be used as
free enzymes or immobilised enzymes.

[0057] The order of the process steps may vary to some extent, e.g. step B
can precede step A and/or step I can precede step H or even step G.

[0058] The process according to the invention results in sufficiently low
amounts of β-glucan and protein, both originated from the oat raw
material, in the suspension. The process is so gentle that there is no
need to remove the bran fraction of the oat material, which contains much
β-glucan, nor to remove the proteins, before performing the
enzymatic treatment according to the present invented process. The
process therefore results in a suspension having a β-glucan content,
originating from the oat raw material, of at most 3.0%, preferably at
most 2.0%, more preferably at most 1.0%, still more preferably at most
0.5% (dwb) and most preferably there is no β-glucan originating from
the oat raw material in the suspension. The enzymes used in the process
according to the invention have substantially no protease activity, i.e.
they do not substantially hydrolyse protein in the oat raw material. The
process therefore results in a suspension having protein originating from
the oat raw material with a degree of hydrolysis of at most 10%,
preferably at most 8%, more preferably at most 6%, still more preferably
at most 4%, still more preferably at most 2%, and most preferably 0% in
the suspension. The suspension contains such protein in an amount of
0.1-20%, preferably in an amount of 0.2-15%, more preferably in an amount
of 0.3-10% and most preferably in an amount of 0.4-5 (dwb).

[0059] The heavier fraction of insolubles in the suspension is separated.
Suitable methods for this process step are decantation, centrifugation
and filtration. An advantage of using a large particle size of the oat
raw material in the process is that this separation step is easy to
accomplish. Preferably the inactivation of the enzymes is performed
before the separation step of the insolubles.

[0060] The suspension may be diluted in case the solid contents is still
too high for the purposed use. It may also be homogenised, pasteurised
and/or UHT treated. It is also possible to include one or several food
ingredients depending on the use of the suspension. The suspension can
also be fermented.

[0061] The invention also relates to a powder produced from the suspension
according to the invention or from the suspension prepared according to
the invention. The powder thus contains enzymatically treated oat raw
material, is optionally fermented and optionally also contains one or
several of the food ingredients. The powder is in substantially dry
state, e.g. containing 0-10%, preferably 0-5% by weight of water. The
powder can be produced by drying the oat suspension by any known
technique, preferably by spray drying.

[0062] The suspension and the powder are useful in various non-dairy
edible compositions, in e.g. non-dairy milk, non-dairy cream, non-dairy
flavoured drinks, non-dairy desserts such as ice-cream-like products, and
fermented non-dairy products such as yoghurt-like products. Thus, it
would be rational to produce a basic suspension or powder, which contains
no food ingredients or only those common to all or at least to most end
products. In the preparation of the basic suspension or powder, only
those process steps would be used, which are common to the preparation of
all or at least to most of the end products. The basic suspension or
powder is then used as starting material in the preparation of the final
product. The still missing food ingredients are added and/or necessary
preparation steps are performed.

[0064] The suspension is especially suitable for use as non-dairy milk
because of the favourable sensory properties. A preferred non-dairy
edible composition is therefore a non-dairy milk comprising the oat
suspension or the powder according to the invention. The non-dairy milk
contains at least one food ingredient selected from the group consisting
of salt, preferably in an amount of 0.01-0.3 g, vegetable oil, preferably
in an amount of 0.1-5 g, calcium, preferably in an amount of 0.05-0.3 g,
vitamin D, preferably in an amount of 0.1-2 μg, and stabiliser,
preferably in an amount of 0.01-2 g per 100 g non-dairy milk. Preferably
the non-dairy milk contains all these food ingredients. The non-dairy
milk can also contain plant sterol and/or plant stanol, preferably in an
amount of 0.1-10 g per 100 g non-dairy milk.

[0065] Another preferred non-dairy edible composition is a non-dairy
cream, such as cooking cream, whipping cream or dessert cream (such as
vanilla custard), comprising the oat suspension or the powder according
to the invention. The non-dairy cream contains at least one food
ingredient selected from the group consisting of sweetening agent such as
saccharose or starch syrup, preferably in an amount of 0.1-10 g;
acidifier, preferably in an amount of 0.05-1 g; emulsifier, preferably in
an amount of 0.01-2 g; stabiliser, preferably in an amount of 0.1-5 g;
salt, preferably in an amount of 0.01-0.3 g; flavouring such as
cream/milk arome or vanilla, preferably in an amount of 0.01-1 g; and
vegetable oil/fat, preferably in an amount of 1-40 g per 100 g non-dairy
cream. The non-dairy cream can also contain plant sterol and/or plant
stanol, preferably in an amount of 0.1-10 g per 100 g non-dairy cream.

[0066] Still another preferred non-dairy edible composition is a non-dairy
flavoured drink comprising the oat suspension or the powder according to
the invention. The non-dairy flavoured drink contains at least one food
ingredient selected from the group consisting of sweetening agent such as
saccharose, preferably in an amount of 0.1-10 g; cocoa powder, preferably
in an amount of 0.5-5 g; vegetable oil, preferably in an amount of 0.1-5
g; calcium, preferably in an amount of 0.05-0.3 g; stabiliser, preferably
in an amount of 0.01-2 g; salt, preferably in an amount of 0.01-0.3 g;
vitamin D, preferably in an amount of 0.1-2 μg; flavouring, preferably
in an amount of 0.01-1 g; vegetable, fruit and/or berry materials,
preferably in an amount of 1-30 g; soluble dietary fibre, preferably in
an amount of 0.01-10 g; and plant sterol and/or plant stanol, preferably
in an amount of 0.1-10 g per 100 g non-dairy flavoured drink. By
flavoured drink is meant a drink containing any component delivering
flavour to the drink, such as cocoa; flavouring; and vegetable, fruit
and/or berry materials.

[0067] Yet another preferred non-dairy edible composition is a spoonable
or drinkable non-dairy yoghurt comprising the oat suspension or the
powder according to the invention. Preferably, the non-dairy yoghurt is
prepared by conventional fermenting techniques. The non-dairy yoghurt
contains at least one food ingredient selected from the group consisting
of sweetening agent such as saccharose, preferably in an amount of 0.1-10
g; emulsifier, preferably in an amount of 0.05-1 g; stabiliser,
preferably in an amount of 0.05-10 g; flavouring, preferably in an amount
of 0.01-1 g; vegetable oil/fat, preferably in an amount of 0.5-5 g;
purified protein such as soy bean protein isolate, preferably in an
amount of 0.1-10 g; fruit and/or berry materials, preferably in an amount
of 1-40 g; soluble dietary fibre, preferably in an amount of 0.01-10 g;
and plant sterol and/or plant stanol, preferably in an amount of 0.1-10 g
per 100 g non-dairy yoghurt. Examples of suitable bacteria that can be
used for the preparation of the non-dairy yoghurt are the cultures used
conventionally for yoghurt preparation, such as lactic acid bacteria and
bifidobacteria.

[0068] The following examples illustrate the present invention without
limiting it.

Example 1

[0069] An oat suspension was prepared of rolled oats and water. Rolled
oats were milled and suspended into water 60° C. (dry matter
content 20%). The particle size was determined by analysing a sample of
the milled oat raw material by a screening technique. 100% of the flour
was retained on a 200 μm screen. The oat raw material was then treated
with α-amylase (Fungamyl 800L, Novozymes, 0.07% of the oat raw
material) and amyloglucosidase (Optidex L-400, Genencor International,
0.18% of the oat raw material) at 60° C. for 3 hours. The enzymes
were then inactivated at 85° C. and the insoluble fraction was
separated by decantation (Foodec 310 decanter). The dry matter content of
the resulting oat suspension was adjusted to 10%.

[0070] The sugar and non-fibre oligosaccharide content and profile of the
oat suspension was analysed by an ion chromatographic method (Dionex
CarboPac PA-100 column, pulse amperometric detector ED50). The protein
content was analysed by the Kjeldahl method, the degree of hydrolysis of
the protein by the OPA method, the starch by the AOAC 996.11 method, and
the β-glucan by the AOAC 995.16 method.

[0071] The sensory properties of the oat suspension were evaluated in
Examples 6 and 7.

Example 2

[0072] An oat suspension was prepared of whole oat flour and water. The
oats were milled by a laboratory mill (Laboratory Mill 3100). 85% of the
oat flour was retained on a 200 μm screen, 65% on a 265 μm screen,
45% on a 400 μm screen; 25% on a 670 μm screen, 5% on a 850 μm
screen and traces on a 1000 μm screen. Oat flour was suspended into
water at 60° C. (dry matter content 20%). The oat raw material was
then treated with α-amylase (Fungamyl 800L, Novozymes, 0.07% of the
oat raw material) and amyloglucosidase (Optidex L-400, Genencor
International, 0.18% of the oat raw material) at 60° C. for 3
hours. The enzymes were then inactivated at 85° C. and the
insoluble fraction was separated by centrifugation. The dry matter
content of the resulting oat suspension was adjusted to 10%. Rape-seed
oil in an amount of 0.5 g and vitamin D in an amount of 0.5 μg per 100
g of the suspension were added.

[0075] The sensory properties of the oat suspension were evaluated in
Example 7.

Example 4

[0076] Mixture of oat bran and rolled oats (bran content 20%) was milled
and the particle size determined as in Example 1. 52% of the milled flour
retained on a 200 μm screen. The flour was suspended into water at
60° C. (dry matter content 20%) and oat suspension prepared as in
Example 1.

[0077] The oat suspension had a mild taste with almost no taste of oats.
The color was somewhat darker than in the oat suspension of example 3,
but still very light and acceptable.

Example 5

Comparative Example

[0078] An oat suspension was prepared of rolled oats and water. The rolled
oats were milled and the milled oat material was subjected to an extra
process step (sieving) to remove larger size particles. The sieving step
removed substantially all particle that were larger than 200 μm. The
flour that passed a 200 μm screen was used in the preparation of the
oat suspension. 51% of this flour passed also a 75 μm screen. The
enzymatic reaction and decantation was done as described in Example 1.
The oat suspension contained more dry matter after the decantation step
than the oat suspensions of Examples 1-4 (13%) and even after diluting to
10% dry matter content the mouthfeel of the oat suspension was slimy.

[0079] The sensory properties of the oat suspension were evaluated in
Example 7.

Example 6

Sensory Analyses

[0080] The sensory properties of the oat suspensions were analysed by a
trained sensory panel (n=23). The oat suspension of Example 1 (sample 1)
was compared to an oat suspension prepared as in Example 2 of WO 95/07628
(sample 2).

[0081] The oat suspension of the current invention contained glucose as
its main sugar, whereas maltose was the main sugar in the oat suspension
of WO 95/07628. The oat suspension of WO 95/07628 contained also
β-glucan and had the taste and aroma of natural oats. The dry matter
content of the both suspensions was adjusted to 7% before the test.

[0082] The panellists were asked to evaluate the colour, structure and
taste of the oat suspensions. The test was done as a pair-wise ranking
test, in which the panellist chose the sample they preferred separately
for each attribute. The panellists were also asked which sample had
stronger taste of oat. The panellists were also asked to rank the samples
1 and 2 according to overall preference. The results are presented in
Table 5.

[0083] Sample 2 had stronger taste of oat according to 74% of the
panellists. The weaker taste of oat in the sample 1 was an advantage and
most of the panellists preferred sample 1 (71% of the panellists, overall
preference). In addition to the weaker taste of oats, sample 1 was
preferred also in other attributes (colour, structure and overall taste).

[0084] Sample 1 (oat suspension of the present invention) was said to have
pleasant structure, colour and taste, balanced taste, less bitterness
than sample 2 and only mild oat taste. The structure and mouthfeel were
said to be pleasant and not too thin.

Example 7

Sensory Analyses

[0085] A trained sensory panel (n=33) evaluated the oat suspensions of
Examples 1, 3 and 5 (samples A, B, C, respectively). The panellists were
asked to drink 0.75 dl of each sample and to evaluate the suitability of
each oat suspension to be used as non-dairy milk (oat milk) to be
consumed together with a meal. The samples were given in a randomised
order. The panellists evaluated the sweetness of the oat suspensions with
a scale from -3 . . . 0 . . . +3, where -3 is not enough sweetness, 0 is
suitable sweetness and +3 is too much sweetness and gave comments about
the samples.

TABLE-US-00007
TABLE 7
Results from the sensory analysis
sample A sample B sample C
scores, mean 0.0 1.6 2.7
comments suitable sweetness good too sweet to be consumed
sweetness for a non-dairy as non-dairy milk
is like milk milk I would not drink
suitable as good mouthfeel might be used for
non-dairy milk is like UHT milk preparing desserts
neutral would be good thick mouthfeel
mild with cocoa only children might
like this
not pleasant

[0086] The oat suspension of Example 1 (sample A) proved to be most
suitable to be consumed as a non-dairy milk (oat milk) together with a
meal. It resembled milk. Also oat suspension of Example 3 (sample B) was
considered to be suitable to be used as a drink, either as a non-dairy
milk or as a drink consumed separately from a meal. It resembled UHT
milk. Oat suspension of Example 5 had highest glucose content and was
considered to be too sweet to be consumed as non-dairy milk. Also the
slimy mouthfeel of the oat suspension of Example 5 was noticed. It was
thought to be suitable for preparing desserts, but not to be consumed as
a drink.

Example 8

[0087] The oat suspension of Example 1 was used to prepare a raspberry
flavoured oat drink.

[0088] The ingredients were mixed and the drink was homogenised and
pasteurised.

Example 9

[0089] The oat suspension of Example 3 was dried (spray drying) into a
powder having a dry matter content of 97% by weight. The powder was used
to prepare a flavoured oat drink containing sea buckthorn berry.

[0102] The ingredients were mixed and the mixture was homogenised and
pasteurised. The mixture was then fermented with lactic acid bacteria and
Bifidobacterium lactis until pH had lowered to about 4.5. Strawberry jam
was added to the fermented mixture in an amount of 17 g per 100 g
non-dairy yoghurt.

Patent applications by Paivi Kuusisto, Naantali FI

Patent applications by Pirjo Alho-Lehto, Vanhalinna FI

Patent applications by RAISIO NUTRITION LTD

Patent applications in class Of farinaceous cereal or cereal material

Patent applications in all subclasses Of farinaceous cereal or cereal material